The field of the present invention is the area of cellulolytic enzymes, nucleotide sequences encoding them and recombinant host cells and methods for producing them.
Cellulosic biomass, photosynthesized by solar energy with CO.sub.2 and H.sub.2 O, is one of the most important renewable energy resources on earth. Its effective utilization through biological processes is one approach to overcoming the shortage of foods, feeds and fuels, expected as a consequence of the explosive increase in human population [Ohmiya et al. (1997) Biotechnol. Gen. Engineer. Rev. 14, 365-414]. Several types of enzymes are required for complete hydrolysis of cellulose to glucose, including endoglucanase, exoglucanase or cellobiohydrolase and .beta.-glucosidase [Filho 1996) Can. J. Microbiol. 42, 1-5].
There is a need in the art for cellulolytic enzymes, for DNA encoding the CelF cellulase of Orpinomyces PC-2 and for methods which enable producing the CelF cellulase in recombinant host cells. Cellulases are useful in the textile and paper industries, as well as in the fuel and chemical production from cellulosic feedstocks.